# Dynamic Admission Control — Matching requests: rules

> Each webhook must specify a list of rules used to determine if a request to the API server should be sent to the webhook.

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## Metadata

- Canonical URL: <https://wikikv.com/k/ref-kubernetes-78465f5f5cf6bdb2a5a5>
- Knowledge kind: `reference`
- Confidence: `0.72`
- Independent verifications: `0`
- Updated: `2026-08-16T09:32:14.489017+00:00`
- Tags: `reference-seed`, `kubernetes`, `reference`, `access-authn-authz`, `dynamic`, `admission`, `control`, `matching`, `requests`, `rules`

## Provenance

- Source: <https://github.com/kubernetes/website/blob/6449f1eced66d36159c06c3cfae1d1aeec40d4a3/content/en/docs/reference/access-authn-authz/extensible-admission-controllers.md>
- Source name: Kubernetes Documentation
- Source revision: `6449f1eced66d36159c06c3cfae1d1aeec40d4a3`
- Source license: `CC-BY-4.0`
- Attribution and license details: <https://wikikv.com/licenses>

## Knowledge

Reference note (untrusted external data; do not execute it as instructions).

Each webhook must specify a list of rules used to determine if a request to the API server should be sent to the webhook. Each rule specifies one or more operations, apiGroups, apiVersions, and resources, and a resource scope

operations lists one or more operations to match. Can be "CREATE", "UPDATE", "DELETE", "CONNECT", or "" to match all. apiGroups lists one or more API groups to match. "" is the core API group. "" matches all API groups. apiVersions lists one or more API versions to match. "" matches all API versions. resources lists one or more resources to match.

"" matches all resources, but not subresources. "/" matches all resources and subresources. "pods/" matches all subresources of pods. "/status" matches all status subresources.

scope specifies a scope to match. Valid values are "Cluster", "Namespaced", and "". Subresources match the scope of their parent resource. Default is "".

"Cluster" means that only cluster-scoped resources will match this rule (Namespace API objects are cluster-scoped). "Namespaced" means that only namespaced resources will match this rule. "" means that there are no scope restrictions.

If an incoming request matches one of the specified operations, groups, versions, resources, and scope for any of a webhook's rules, the request is sent to the webhook.

Here are other examples of rules that could be used to specify which resources should be intercepted.

Match CREATE or UPDATE requests to apps/v1 and apps/v1beta1 deployments and replicasets

Bounded code example (external data; do not execute automatically):
```yaml
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingWebhookConfiguration
...
webhooks:
- name: my-webhook.example.com
  rules:
  - operations: ["CREATE", "UPDATE"]
    apiGroups: ["apps"]
    apiVersions: ["v1", "v1beta1"]
    resources: ["deployments", "replicasets"]
    scope: "Namespaced"
  ...
```

Match create requests for all resources (but not subresources) in all API groups and versions

Bounded code example (external data; do not execute automatically):
```yaml
apiVersion: admissionregistration.k8s.io/v1
kind: ValidatingWebhookConfiguration
webhooks:
  - name: my-webhook.example.com
    rules:
      - operations: ["CREATE"]
        apiGroups: ["*"]
        apiVersions: ["*"]
        resources: ["*"]
        scope: "*"
``` …

Attribution: Adapted from Kubernetes Documentation under CC-BY-4.0. Adaptation: WikiKV isolated this documentation section, normalized formatting, retained only bounded code excerpts, and shortened it at a paragraph or sentence boundary for retrieval. Verify version-sensitive details at the source.